A filter that takes another filter and always returns the opposite of another filter. This is
useful where you have two filters (i.e. one for header and one for footer) and want to ensure
that nothing ever has false returned for both cases.

acceptOtherJavaScript

Whenever a render*JavaScript method on IHeaderResponse is called that is not a
ResourceReference (i.e. IHeaderResponse.renderOnDomReadyJavaScript(String)), this
method determines if the script should be bucketed with other things in this filter.
Note that calls to IHeaderResponse.renderJavaScriptReference(String url) are also
filtered with this method since there is no actual ResourceReference to pass